java - 将列表 View 的点击值传递给具有共享首选项的另一个 Activity

我有三个活动。

我想将点击数据从第一个活动传递到第三个活动。

第一（单击）>第二（单击）>第三

我的问题是：在SwipeNavAdapter

String data1 = sharedPreferences.getString(ListNavAdapter.ID_EXTRA, "")不显示ListNavAdapter中的列表，但显示CourseAdapter中的列表。我想从ListNavAdapter中的SwipeNavAdapter中获得单击的列表项。

首先：ListNavAdapter

SQLiteDatabase sqLiteDatabase = SqliteDatabase.getInstance(this.getContext()).getWritableDatabase();
Cursor cursor = sqLiteDatabase.rawQuery("SELECT CHAPTER FROM BOOK GROUP BY CHAPTER order by _id", new String[]{});

 if (cursor.getCount() == 0) {
 //
 } else {
     while (cursor.moveToNext()) {
         listItem.add(cursor.getString(0));
     }
     arrayAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, listItem);
     listView.setAdapter(arrayAdapter);
 }
listView.setOnItemClickListener(new OnItemClickListener() {
     @Override
     public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
         SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getContext());
         String achal=(String)adapterView.getItemAtPosition(i);
         SharedPreferences.Editor editor = sharedPreferences.edit();
         editor.putString(ID_EXTRA, achal);
         editor.apply();
         Intent intent=new Intent(getActivity(), Course.class);
         intent.putExtra(ID_EXTRA, String.valueOf(l));
         startActivity(intent);
     }
 });

第二：CourseAdapter

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getContext());
String  data = sharedPreferences.getString(ListNavAdapter.ID_EXTRA, "") ;
SQLiteDatabase sqLiteDatabase = SqliteDatabase.getInstance(this.getContext()).getWritableDatabase();
Cursor cursor = sqLiteDatabase.rawQuery("SELECT TEXT_NO FROM BOOK WHERE CHAPTER='" + data + "' ORDER BY _id", new String[]{});

if (cursor.getCount() == 0) {
   //
} else {
    while (cursor.moveToNext()) {
        listItem.add(cursor.getString(0));
    }
    arrayAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, listItem);
    listView.setAdapter(arrayAdapter);
}
listView.setOnItemClickListener(new OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getContext());
            String achal1=(String)adapterView.getItemAtPosition(i);
            SharedPreferences.Editor editor = sharedPreferences.edit();
            editor.putString(ID_EXTRAA, achal1);
            editor.apply();
            Intent intent=new Intent(getActivity(), SwipeNav.class);
            intent.putExtra(ID_EXTRAA, String.valueOf(l));
            startActivity(intent);
        }
    });

第三：SwipeNavAdapter

@Override
public Fragment getItem(int i) {
    SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);
    String  data1 = sharedPreferences.getString(ListNavAdapter.ID_EXTRA, "") ;
    System.out.println(data1);
    ArrayList<String> listItem1 = new ArrayList<String>();
    Cursor cursor1 = sqLiteDatabase.rawQuery("SELECT TEXT FROM BOOK WHERE CHAPTER='" + data1 + "'", new String[]{});
    if (cursor1.getCount() == 0) {
        ///
    } else {
        while (cursor1.moveToNext()) {
            listItem1.add(cursor1.getString(0));
        }
    }
    Object[] mStringArray1 = listItem1.toArray();
    Fragment fragment = new AFragment();
    Bundle args = new Bundle();
    assert mStringArray1 != null;
    args.putString(AFragment.ARG_OBJECT1, (String)mStringArray1[i]);
    fragment.setArguments(args);
    return fragment;
}


@Override
public int getCount() {
    SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);
    String  data1 = sharedPreferences.getString(ListNavAdapter.ID_EXTRA, "") ;
    SQLiteDatabase sqLiteDatabase = SqliteDatabase.getInstance(context).getWritableDatabase();
    ArrayList<String> listItem = new ArrayList<>();
    Cursor cursor = sqLiteDatabase.rawQuery("SELECT TEXT FROM BOOK WHERE CHAPTER='" + data1 + "'", new String[]{});
    while (cursor.moveToNext()) {
        listItem.add(cursor.getString(cursor.getColumnIndex("TEXT")));
    }
    return listItem.size();
}

最佳答案

我的问题是：在SwipeNavAdapter中
  
  字符串data1 = sharedPreferences.getString（ListNavAdapter.ID_EXTRA，
  “”）不显示ListNavAdapter中的列表，但显示中的列表
  CourseAdapter。我想从ListNavAdapter获得单击的列表项
  在SwipeNavAdapter中。


我假设您正在使用SharedPreferences和CourseAdapter中使用的相同键覆盖ListNavAdapter中的值。确保ID_EXTRA中的ListNavAdapter键和ID_EXTRAA中的CourseAdapter键是不同的。

如果将值添加到sharedPreference的相同键下，则该值将被覆盖。